Impact of currently used or potentially useful insecticides for canola agroecosystems on Bombus impatiens (Hymenoptera: Apidae), Megachile rotundata (Hymentoptera: Megachilidae), and Osmia lignaria (Hymenoptera: Megachilidae).

Pest management practices may be contributing to a decline in wild bee populations in or near canola (Brassica napus L.) agroecosystems. The objective of this study was to investigate the direct contact toxicity of five technical grade insecticides--imidacloprid, clothianidin, deltamethrin, spinosad, and novaluron--currently used, or with potential for use in canola integrated pest management on bees that may forage in canola: common eastern bumble bees [Bombus impatiens (Cresson); hereafter bumble bees], alfalfa leafcutting bees [Megachile rotundata (F.)], and Osmia lignaria Cresson. Clothianidin and to a lesser extent imidacloprid were highly toxic to all three species, deltamethrin and spinosad were intermediate in toxicity, and novaluron was nontoxic. Bumble bees were generally more tolerant to the direct contact applications > O. lignaria > leafcutting bees. However, differences in relative toxicities between the three species were not consistent, e.g., whereas clothianidin was only 4.9 and 1.3x more toxic, deltamethrin was 53 and 68x more toxic to leafcutting bees than to bumble bees and O. lignaria, respectively. Laboratory assessment of direct contact toxicity, although useful, is only one measure of potential impact, and mortality under field conditions may differ greatly depending on management practices. Research conducted using only honey bees as the indicator species may not adequately reflect the risk posed by insecticides to wild bees because of their unique biology and differential susceptibility. Research programs focused on determining nontarget impact on pollinators should be expanded to include not only the honey bee but also wild bee species representative of the agricultural system under investigation.

Detection of an explosive simulant via electrical impedance spectroscopy utilizing the UiO-66-NH2 metal-organic framework.

Electrical impedance spectroscopy, in conjunction with the metal-organic framework (MOF) UiO-66-NH2, is used to detect trace levels of the explosive simulant 2,6-dinitrotoluene. The combination of porosity and functionality of the MOF provides an effective dielectric structure, resulting in changes of impedance magnitude and phase angle. The promising data indicate that MOFs may be used in low-cost, robust explosive detection devices.

Evaluation of sampling methodology for determining the population dynamics of onion thrips (Thysanoptera: Thripidae) in Ontario onion fields.

Onion thrips, Thrips tabaci Lindeman, are an economic pest of alliums worldwide. In Ontario onion-growing regions, seasonal abundance and population trends of onion thrips are not well known. The objectives of this research were to investigate onion thrips population dynamics by using both white sticky traps and plant counts, to gain insight into flight height, and to determine the genus and sex of thrips fauna present in monitored fields. Adult thrips were captured on white sticky traps placed in two commercial onion fields in the Thedford-Grand Bend Marsh region as early as mid-May in 2001, 2002, and 2003. Thrips were not recorded on onion plants in these fields until late June and early July. A comparison of sticky trap captures to plant counts revealed a strong, positive correlation, indicating that sticky traps, which consistently detected thrips earlier than plant counts, could be used instead of plant counts early in the season to monitor onion thrips populations. Pole traps placed in onion and an adjacent soybean, Glycine max (L.) Merr., field revealed that regardless of crop type, most thrips were captured 0.7-0.95 m above the soil surface. During this study, 70% of 137,000 thrips captured on sticky traps and 89% of 1,482 thrips captured in pan traps were female onion thrips. No male onion thrips were identified in this study: most of the remaining thrips were Frankliniella spp.

Relationship of genetically transmitted alpha EEG traits to anxiety disorders and alcoholism.

We tested the hypothesis that a heritable EEG trait, the low voltage alpha (LV), is associated with psychiatric disorders. Modest to moderate evidence for genetic linkage of both panic disorder and the low voltage alpha trait to the same region of chromosome 20q has recently been reported, raising the issue of whether there is a phenotypic correlation between these traits. A total of 124 subjects including 50 unrelated index subjects and 74 relatives were studied. Alpha EEG power was measured and EEG phenotypes were impressionistically classified. Subjects were psychiatrically interviewed using the SADS-L and blind-rated by RDC criteria. Alcoholics were four times more likely to be LV (including so-called borderline low voltage alpha) than were nonalcoholic, nonanxious subjects. Alcoholics with anxiety disorder are 10 times more likely to be LV. However, alcoholics without anxiety disorder were similar to nonalcoholics in alpha power. An anxiety disorder (panic disorder, phobia, or generalized anxiety) was found in 14/17 LV subjects as compared to 34/101 of the rest of the sample (P < 0.01). Support for these observations was found in the unrelated index subjects in whom no traits would be shared by familial clustering. Lower alpha power in anxiety disorders was not state-dependent, as indicated by the Spielberger Anxiety Scale. Familial covariance of alpha power was 0.25 (P < 0.01). These findings indicate there may be a shared factor underlying the transmissible low voltage alpha EEG variant and vulnerability to anxiety disorders with associated alcoholism. This factor is apparently not rare, because LV was found in approximately 10% of unrelated index subjects and 5% of subjects free of alcoholism and anxiety disorders.

The in vitro radiobiology of astatine-211 decay.

Chinese hamster V79 cells in culture were exposed to astatine-211, an alpha-particle-emitting radiohalogen. The dose-log survival response was linear with no detectable shoulder. Cells in monolayers had a D0 of 1.0 microCi/ml. Suspended cells had a D0 of 0.60 microCi/ml with a cellular uptake of 2.5 fCi/cell; this is equal to approximately 1.5 alpha-particle traversals per cell nucleus. The frequencies of chromosome and chromatid breaks were linear with dose, but the number declined rapidly with time. These data are discussed in relation to published alpha-particle beam studies and the potential use of 211At in radionuclide therapy.

Psychophysiological responses to imagined infidelity: the specific innate modular view of jealousy reconsidered.

Three studies measured psychophysiological reactivity (heart rate, blood pressure, and electrodermal activity) while participants imagined a mate's infidelity. The specific innate modular theory of gender differences in jealousy hypothesizes that men are upset by sexual infidelity and women are upset by emotional infidelity, because of having faced different adaptive challenges (cuckoldry and loss of a mate's resources, respectively). This view was not supported. In men, sexual-infidelity imagery elicited greater reactivity than emotional-infidelity imagery. But, sexual imagery elicited greater reactivity even when infidelity was not involved, suggesting that the differential reactivity may not specifically index greater jealousy. In two studies with reasonable power, women did not respond more strongly to emotional infidelity. Moreover, women with committed sexual relationship experience showed reactivity patterns similar to those of men. Hypothetical infidelity self-reports were unrelated to reactivity.

Cardiovascular responses of embarrassment and effects of emotional suppression in a social setting.

The cardiovascular effects of embarrassment and of attempts to suppress embarrassment were examined. In 2 studies, embarrassment was associated with substantial increases in systolic and diastolic blood pressure, which monotonically increased over a 2-minute embarrassment period. In contrast, heart rate (HR) rose significantly during the 1st minute of embarrassment but returned to baseline levels during the 2nd minute. This pattern of reactivity may be distinctive. The effects of trying to suppress emotion in an interpersonal situation were also tested. Relative to the no-suppression group, suppression participants showed greater blood pressure during embarrassment and during posttask recovery. Suppression did not significantly affect HR. Possible mechanisms for these results, including passive coping, are discussed. Nonverbal behavior was also examined.

Can a machine tickle?

It has been observed at least since the time of Aristotle that people cannot tickle themselves, but the reason remains elusive. Two sorts of explanations have been suggested. The interpersonal explanation suggests that tickling is fundamentally interpersonal and thus requires another person as the source of the touch. The reflex explanation suggests that tickle simply requires an element of unpredictability or uncontrollability and is more like a reflex or some other stereotyped motor pattern. To test these explanations, we manipulated the perceived source of tickling. Thirty-five subjects were tickled twice--once by the experimenter, and once, they believed, by an automated machine. The reflex view predicts that our "tickle machine" should be as effective as a person in producing laughter, whereas the interpersonal view predicts significantly attenuated responses. Supporting the reflex view, subjects smiled, laughed, and wiggled just as often in response to the machine as to the experimenter. Self-reports of ticklishness were also virtually identical in the two conditions. Ticklish laughter evidently does not require that the stimulation be attributed to another person, as interpersonal accounts imply.

Spontaneous allocation of visual attention: dominant role of uniqueness.

Common sense suggests that unique or abruptly changing (transient) elements in a visual scene often draw attention involuntarily. Visual search studies paint a seemingly different picture, however Unique items usually draw attention involuntarily only when observers seek a unique target. One type of transient--abrupt onsets--draws attention involuntarily, but only when the observer is seeking an onset (Folk, Remington, & Johnston, 1992). One way of reconciling common-sense with these findings is to suppose that when people view a scene with no specific goal or task, they adopt a default set, which might prioritize novelty and/or transients. In two experiments, 336 subjects saw a single display of six items for 900 msec, expecting to have to describe it (Experiment 1) or make an aesthetic judgment about it (Experiment 2). One item in the display was either uniquely flashing (surrounded by static items) or uniquely static (surrounded by flashing items). In both studies, the unique item, even if static, was more often reported than the non-unique item, with flashing items enjoying an additional advantage.

Neurocognitive impairment due to chronic alcohol consumption in an American Indian community.

OBJECTIVE: Studies have shown that clinically ascertained alcoholics tend to have lower scores than nonalcoholics on cognitive performance tests, particularly the Block Design (BD) and Digit Symbol (DS) tests of the Weschler Adult Intelligence Scale-Revised (WAIS-R). The aim of this study was to determine whether similar differences are found in a community sample of Plains Indian men and women with an episodic pattern of drinking and a high lifetime prevalence of alcoholism (71% for men, 44% for women). METHOD: We administered a truncated form of the WAIS-R to 334 members of a Plains Indian tribe (197 women and 137 men). Blind-rated psychiatric diagnoses were assigned according to Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM-III-R) criteria and based on the Schedule for Affective Disorders, Lifetime Version (SADS-L) interview. We compared 68 currently drinking alcoholics (38 men and 30 women), 116 abstaining alcoholics (59 men and 57 women) and 150 nonalcoholics (40 men and 110 women). RESULTS: Current and past heavy drinking had no impact on WAIS-R scores in women. Male alcoholics who were abstinent > or = 2years had similar scores to nonalcoholic men. Male current drinkers showed a trend for lower overall verbal and performance (PIQ) scores and BD performance subtest. Further analysis showed that drinking for > or = 15 years was significantly associated with reduced DS in male current drinkers. CONCLUSIONS: These findings suggest that for the men in this community sample, the impact on PIQ is due to the direct effect of chronic alcohol consumption on cognitive performance and is at least partially reversible after 2 years of abstinence.

Does a reduced sensitivity to bitter taste increase the risk of becoming nicotine addicted?

Cigarette smoking appears to be on the increase in adolescents. The initiation of regular smoking nearly always begins before adulthood. It is therefore crucial to find ways of identifying those children most vulnerable to nicotine addiction and prioritizing them for preventive measures. We hypothesized that individuals who, in a simple taste test, perceive phenylthiocarbamide (PTC) as bitter may find the taste of cigarettes aversively bitter and could therefore have a reduced vulnerability to nicotine addiction compared to nontasters, who would be the group at greater risk of addiction. We studied 242 Plains American Indians, 136 women and 106 men aged 18-59 years, and found that (allowing for gender differences and the possible direct effects of smoking on taste) the proportion of PTC nontasters to tasters in smokers, even light smokers, was significantly greater than in both nonsmokers and social smokers (chi2= 15.875, 4 df; P=.003), suggesting that nontasters, who are not aversive to the bitter taste of cigarettes, may be more at risk for heavy smoking and therefore more vulnerable to nicotine addiction.

Pyrethroid insecticide residues on vegetable crops.

Pyrethroid insecticides were applied on various vegetable crops as foliar treatments to determine dissipation rates. On Chinese broccoli (Guy Lon), Chinese mustard (Pak Choi) and Chinese cabbage (Kasumi, napa), fenvalerate was persistent with residues of 0.10, 0.14 and 0.11 mg kg-1, respectively, by day 21. Cypermethrin residues on head lettuce were below 0.1 mg kg-1 by day 10 but on the leafier romaine and endive varieties it was more persistent and required 14-19 days to dissipate below this concentration. After three applications, residues of cypermethrin in harvested carrots and of permethrin in eggplant were not detected on the day of application. On asparagus, deltamethrin and cypermethrin residues declined to less than 0.1 mg kg-1 by days 1 and 2, respectively; permethrin was more persistent, requiring more than 2 days to decline to less than 0.1 mg kg-1. Deltamethrin on dry (cooking) and Spanish onions was not detected on the day of application. On tomatoes, the concentration of permethrin was 0.093 mg kg-1 on the day of application and declined to about 0.05 mg kg-1 after 2-4 days. In general, permethrin, cypermethrin and deltamethrin residues declined to acceptable concentrations within an acceptable pre-harvest interval. Fenvalerate may be too persistent on these speciality crops unless a maximum residue limit > 0.1 mg kg-1 is permitted.

Measurement of absorbed dose from radionuclide solutions mixed intimately with the FBX dosimeter.

Chemical dosimeters are used widely for accurate measurement of large radiation doses due to external beam irradiation from radionuclide sources and from particle accelerators. Their use for measurement of absorbed doses from radioactive solutions mixed in the dosimeter solution was reported as early as 1952, but the large activities needed to produce suitable absorbance values in the relatively insensitive dosimeters of that time discouraged further work. This manuscript reports the results of an investigation into the suitability of the ferrous sulfate-benzoic acid-xylenol orange (FBX) dosimeter for measurement of small absorbed doses caused by radionuclide solutions mixed with the dosimeter solution. The FBX dosimeter exhibited a linear dose response as a function of activity for two common radiopharmaceuticals, 99mTc sodium pertechnetate and 131I sodium iodide. Conditions under which the FBX dosimeter may be used with radionuclide solutions were studied and were found to be amenable to routine use by laboratories possessing relatively unsophisticated instrumentation. That any radionuclide could be studied using this dosimeter appears likely.

Gastrointestinal decontamination. Which method is best?

Why has ipecac syrup become less popular in emergency management of poisoning and overdose? When should gastric lavage, activated charcoal, cathartics, or a combination of methods be used? Which patients are candidates for whole-bowel irrigation with polyethylene glycol-electrolyte solution? Drs Harris and Kingston answer these questions and present their recommendations for each of the available management options.

Dosimetry considerations in far field microwave exposure of mammalian cells.

A circulating water bath exposure system has been designed for in vitro radiofrequency radiation (RFR) exposure studies in the 915 to 2450 MHz range. A Styrofoam float, in which 10 T-25 plastic tissue culture flasks are embedded, is rotated at approximately 20 rpm in a Plexiglas water bath at a distance beneath a rectangular horn. The continuous circular rotation of the flasks is designed to "average out" the heterogeneity present in stationary flask exposures. The rotation also serves to prevent the establishment of chemical gradients in the medium within the flasks. Several factors have been demonstrated to affect the specific absorption rate (SAR) measured in the medium in the exposed flasks. These factors include: 1) the position of the exposure flasks relative to the long axis of the antenna horn; 2) whether the flasks are exposed while stationary or in rotation; 3) the volume of the medium contained in the flask; and 4) the depth in the medium in the flask at which temperatures for SAR calculation are measured. The presence of cells in the exposure flask (as attached monolayer or cell suspension) did not result in an SAR different from that measured in the same volume of medium without cells present.

The bromodomain and extra-terminal inhibitor CPI203 enhances the antiproliferative effects of rapamycin on human neuroendocrine tumors.

Endogenous c-MYC (MYC) has been reported to be a potential pharmacological target to trigger ubiquitous tumor regression of pancreatic neuroendocrine tumors (PanNETs) and lung tumors. Recently inhibitors of bromodomain and extra-terminal (BET) family proteins have shown antitumor effects through the suppression of MYC in leukemia and lymphoma. In this paper, we investigated the antitumor activity of a BET protein bromodomain inhibitor (BETi) CPI203 as a single agent and in combination with rapamycin in human PanNETs. We found that exposure of human PanNET cell lines to CPI203 led to downregulation of MYC expression, G1 cell cycle arrest and nearly complete inhibition of cell proliferation. In addition, overexpression of MYC suppressed the growth inhibition caused by CPI203 and knockdown of MYC phenocopied the effects of CPI203 treatment. These findings indicate that suppression of MYC contributed to the antiproliferative effects of BETi inhibition in human PanNET cells. Importantly, CPI203 treatment enhanced the antitumor effects of rapamycin in PanNET cells grown in monolayer and in three-dimensional cell cultures, as well as in a human PanNET xenograft model in vivo. Furthermore, the combination treatment attenuated rapamycin-induced AKT activation, a major limitation of rapamycin therapy. Collectively, our data suggest that targeting MYC with a BETi may increase the therapeutic benefits of rapalogs in human PanNET patients. This provides a novel clinical strategy for PanNETs, and possibly for other tumors as well.